The decomposition of HI(g) is represented by the equation:

Question

2HI(g) <-> H2(g) + I2(g)

Kc= 64 at 25°C.

If the equilibrium concentrations of H2 and I2 at 400°C are found to be [H2] = 5.4x10-4 M and [I2] = 8.8x10-3 M, what is the equilibrium concentration of HI?

Answer 1

Set up an ICE chart, substitute into Kc, and solve for HI.
Post your work if you get stuck.

Answer 2

2.7 × 10-4